SD-WAN and Out-Of-Band

SD-WAN Deployments Need Out-of-Band Visibility

SD-WAN provides lower cost, secure network connections across corporate and regional locations, based on the simplified architecture of SDN. But without an Out-of-Band backup, SD-WAN has an Achilles heel.

Flexible Networks Across Remote Locations

The Tale of Two SD-WAN Deployments Infographic. Click thumbnail to enlarge.

SD-WAN is the application of Software Defined Networking (SDN) to create a smarter, more agile Wide Area Network, able to support the increasingly sophisticated distribution of networking devices across multiple locations and remote sites, whether that’s branch offices, manufacturing locations or retail stores. It provides the flexibility to change the network configuration and logical topology without changing the physical infrastructure, and allows the creation of virtual network groups across sites, independent of where people are geographically located.

The local router is a more sophisticated device in a SD-WAN deployment, incorporating advanced software capabilities to provide a flexible configuration across the network. Moving away from the vertically integrated ecosystems of the past, these CPE routers can now be based on commodity hardware, reducing costs and expanding the available options.

Software-Defined Networking (SDN) is an architecture for building network infrastructure that explicitly separates the control/management plane from the data forwarding layer. The network is managed by the SDN controller, a piece of software that interacts with the switching fabric through APIs and standard protocols. In traditional infrastructures, the switching hardware fabric, the higher level protocols and the management software are often vertically integrated and reside in an embedded networking appliance. Separating the control plane (mostly software) from the underlying switch fabric allows for more flexibility and removes the dependence on hardware from a single vendor ecosystem that was typical with previous networking systems.

Smart Out-of-Band for a Resilient SD-WAN

This new flexibility brings with it a heightened need for remote hands to manage the on-site devices. With the increased sophistication of the SD-WAN hardware – specifically the advanced routers located at each site – the need for “always-on” access to that hardware is more critical than ever. In many locations, the level of technical ability will be limited, so when an issue occurs the network team must be able to manage the equipment remotely. An out-of-band network provides that visibility and security.

Initial Implementation

During the initial roll out and migration from the previous WAN, using a console server can avoid an expensive truck roll. Ship an Opengear Resilience Gateway to site, and provision the network from a central NOC without the need to send an experienced network engineer to each location. Embedded cellular in the Opengear unit enables this process over 4G-LTE if the primary network is not available during the transition.

As with any new implementation, the first few months may be unstable with frequent updates and glitches, such as encapsulation issues disrupting connectivity. Smart out-of-band allows you to automate these updates and remediate issues without sending someone to site.

Steady Operation

A benefit of SD-WAN is the ability to aggregate multiple circuits for load balancing and redundancy, but the SD-WAN router can still be a single-point-of-failure. A single event can still cause simultaneous failures in multiple circuits (for example, severed cables into the facility), if a truly separate path is not in the mix. Smart out-of-band offers Failover to CellularTM, to ensure your SD-WAN continues to operate when all other circuits are unavailable.

With an Opengear console server at every SD-WAN location, and each node part of a Lighthouse 5 Centralized Management system, NetOps staff at the Data Center or NOC can remotely manage, automate and orchestrate the network devices without the need for experienced technical staff at each site.

An out-of-band management network provides the guaranteed access and high reliability to make SD-WAN a low-risk option.